The present invention relates to a loading dock for large trucks. More specifically, a loading dock which provides an air tight seal during the loading and unloading of potato trucks at a potato warehouse. The Self Sealing Potato Truck Loading Dock provides a method of obtaining such a seal around the unique rear configuration of potato trucks used in the transportation of the harvested crop.
The loading docks that are currently used in the loading and unloading of trucks consist of two different types. The first of these consists of compressible pads that are fixed around the outside edge of the warehouse door. With this type of sealing mechanism, a truck backs up against these pads and the most rearward surface of the truck box engages and compresses these pads, thereby forming the desired isolation of the inside of the warehouse and the truck from the outside air. The second type uses a fabric curtain around the warehouse door. When engaged, the fabric curtain is draped around the outside of the most rearward portion of the truck box, thereby creating the desired air seal.
In the past, potato trucks were forced to use one of the above two types of sealing mechanisms that were designed for use with standard, or rectangular, truck boxes. While these standard loading docks provide an adequate seal for regular truck boxes, the box of a potato truck presents special problems in this respect. The potato truck box is not rectangular in its longitudinal profile as is the box of a standard truck. Rather, it more closely resembles a diamond shape with its side walls angled toward the center of the box at their upper and lower extremes.
Also, the potato truck box is equipped with a conveyor at the bottom center of the box which runs the entire length of the box. The conveyor is used to move the potatoes from the box to the rear during unloading. The conveyor extends beyond the most rearward portion of the potato truck's box and this, along with the angled sides of the box, creates the problem that makes any presently employed method of providing an air tight seal between an unloading truck and a warehouse ineffective when used with a potato truck.
The providing of an air tight seal, and thereby isolating the interior of the warehouse and the inside of the truck box from the outside air, has very important safety considerations for those involved in the loading and unloading of potato trucks. The harvesting of potatoes takes place in the fall of the year when the weather is typically damp and cool and very often the potatoes are transported from warehouses to processing plants during the cold winter months. The difference in air temperature from the outside to the inside of the warehouse often creates a thick fog in and around the work area when there is an ineffective seal between the box of the truck and the warehouse. The presence of the fog has the effect of greatly reducing the visibility in the work area and often results in accidents due to the nature of the heavy equipment used in and around the loading dock area.
From the forgoing discussion, it can be seen that a method of providing an effective air tight seal between the box of an unloading or loading potato truck and the loading dock of a warehouse is highly desirable. The prior art is ineffective in this application because the designs are intended to be used with the rectangular shapes of standard truck boxes. This creates a problem in their use with a potato truck box because it leaves areas around the box completely open to the outside air due to the irregular shape of a potato truck box. Thus, allowing the outside air to enter the warehouse and create the dangerous working conditions of fog limited visibility.
The present invention accomplishes the described objective by providing a series of double layered sealing canvases that effectively and completely encircle the irregular shape of the rear surface of the box of a potato truck. This configuration provides an air tight seal between the cold and damp outside air and the interior of the warehouse. The present invention also has the added advantage of being compatible with standard, rectangular truck boxes.